It is rare for McIlroy to toil through an entire tournament. What is more common is a ruinous spell of nine holes or fewer, which undermines the Northern Irishman’s hopes of endorsing his ability with more tangible reward than has already been the case.

When McIlroy gets into these ruts, they are more costly than need be the case. A 72 rapidly turns into a 78. Tournament challenges disintegrate as others are holding things together with an acceptance that setbacks will occur.

To his eternal credit, McIlroy is routinely able to bounce back from these runs with impressive scoring spells. By that stage, however, he is trying to secure a top 10 place rather than a bigger prize.

“It might be a little bit to do with once I get on a run, I’m maybe trying a little too hard to get out of it and that compounds the issue,” McIlroy acknowledged. “I need to figure out these nine holes of golf where instead of it being four over or five over, I can maybe be one or two over, just limiting the damage a little bit.

“There’s just been runs of holes in tournaments where I haven’t played so well. I have shot four or five over in the space of nine holes, and that’s really just derailed my tournament.”

Augusta National was the scene of McIlroy’s most costly tumble, when he dropped six shots in three holes during the closing stretch of the 2011 Masters. Nobody who watched that episode could have failed to feel sympathy for a player whose game imploded so spectacularly in front of a worldwide audience.

If McIlroy ever manages to win a Masters, and the odds are in favour of him doing so, he will inevitably glance back to that horrible experience.

“I seem to throw in a high number every year,” said McIlroy of the Masters. “Last year it was a 79, this year it was a 77. At least it’s getting a little better.

“It’s about turning those 77s and the high ones into 72s or 73s – that’s the real key for me around Augusta National.

“I know when I get it going I can make a few birdies and I can shoot the scores. But it’s just making sure that I don’t let a round get away from me. I’ve been saying that the last three years I’ve been coming to the Masters but I still haven’t figured out how to do it.”

This US Open again offered such evidence. McIlroy began round three within touching distance of the leaders but reached the turn in 40. A three-putt bogey on the 2nd began this tale of woe.

There was an element of bad fortune attached to the run. On the 6th, a perfectly played tee shot somehow ran all the way through the putting surface. But there was also carelessness – McIlroy left a bunker shot on the 5th in the trap and, by his own admission, came perilously close to doing it a second time.

“I just need to curb my enthusiasm at times,” said McIlroy. “You’re standing with a 7-iron in your hand on that 5th hole, for example, and know that actually missing the green short right isn’t a bad shot. Instead of trying to hit the perfect shot, landing it in the middle of the green.”

What is known is that Nicklaus asked McIlroy: “How the hell do you go from scoring 63 on a Thursday to 78 on a Friday?” That was a reference to the Memorial Tournament last month where McIlroy did precisely that.

At Memorial, McIlroy embarked on an astonishing Friday run which saw him lie level par through three holes but six over after six. He played his front nine in 43.

The most glaring McIlroy figures of this year to date came at Sawgrass in the Players Championship, where the 25-year-old tied for sixth.

McIlroy played the back nine in an aggregate of 17 under par. On the front? Eight over.

“I just feel like I see one bad shot and then it turns into another and then another,” said McIlroy at the time. “It’s not like a loss of confidence but I just get into these little runs where I can’t seem to hit a solid shot. If I miss it, I miss it in the wrong spot.”

McIlroy’s putting and wedge play does occasionally let him down. The clear evidence, though, points to matters of the mind in response to body blows being the far more pertinent issue. Nicklaus’s advice should prove invaluable in the longer-term.